Jason Torchinsky told a three-judge panel -- Judge Paul Neimeyer, of the 4th Circuit Court of Appeals; Judge Alexander Williams, of Maryland; and Judge Roger Titus, of Maryland -- that Maryland should have three majority-minority congressional districts instead of two, because of growth in the state's minority population based on the 2010 census.

Torchinsky said the Democrat-controlled General Assembly failed to make Rep. Steny Hoyer's district a majority-minority one in order to protect the high-ranking incumbent from a black challenger.

But Dan Friedman, an assistant attorney general defending the map, pointed out that Hoyer has always run well in the state's 5th congressional district, which has a large number of black voters. He also said the map approved by the General Assembly in October was supported by many black lawmakers.

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